A nozzle is generally made of
Cylindrical shape
Convergent shape
Divergent shape
Convergent-divergent shape
Correct Answer :
B. Convergent shape
Related Questions
In a footstep bearing, if the speed of the shaft is doubled, then the torque required to overcome the viscous resistance will be
Double
Four times
Eight times
Sixteen times
A weir is said to be narrow-crested weir, if the width of the crest of the weir is __________ half the height of water above the weir crest.
Equal to
Less than
More than
None of these
When a cylindrical vessel, containing some liquid, is rotated about its vertical axis, the liquid surface is depressed down at the axis of its rotation and rises up near the walls of the vessel on all sides. This type of flow is known as
Steady flow
Turbulent flow
Vortex flow
Uniform flow
The Bernoulli's equation is based on the assumption that
There is no loss of energy of the liquid flowing
The velocity of flow is uniform across any cross-section of the pipe
No force except gravity acts on the fluid
All of the above
Ratio of inertia force to elastic force is known as
Mach number
Froude number
Reynolds number
Weber's number
During the opening of a valve in a pipe line, the flow is
Steady
Unsteady
Uniform
Laminar
The diameter of the nozzle (d) for maximum transmission of power is given by (where D = Diameter of pipe, f = Darcys coefficient of friction for pipe, and l = Length of pipe)
d = (D⁵/8fl)1/2
d = (D⁵/8fl)1/3
d = (D⁵/8fl)1/4
d = (D⁵/8fl)1/5
Cavitation is caused by
High velocity
High pressure
Weak material
Low pressure
At the center line of a pipe flowing under pressure where the velocity gradient is zero, the shear stress will be
Minimum
Maximum
Zero
Could be any value
The rise of liquid along the walls of a revolving cylinder about the initial level is __________ the depression of the liquid at the axis of rotation.
Same as
Less than
More than
None of these
Falling drops of water become spheres due to the property of
Adhesion
Cohesion
Surface tension
Viscosity
An orifice is said to be large, if
The size of orifice is large
The velocity of flow is large
The available head of liquid is more than 5 times the height of orifice
The available head of liquid is less than 5 times the height of orifice
The maximum discharge over a broad crested weir is
0.384 Cd × L × H1/2
0.384 Cd × L × H3/2
1.71 Cd × L × H1/2
1.71 Cd × L × H3/2
The ratio of absolute viscosity to mass density is known as
Specific viscosity
Viscosity index
Kinematic viscosity
Coefficient of viscosity
An ideal flow of any fluid must satisfy
Pascal law
Newton's law of viscosity
Boundary layer theory
Continuity equation
According to Bernoulli's equation
Z + p/w + v²/2g = constant
Z + p/w - v²/2g = constant
Z - p/w + v²/2g = constant
Z - p/w - v²/2g = constant
The discharge over a right angled notch is (where H = Height of liquid above the apex of notch)
(8/15) Cd. 2g. H
(8/15) Cd. 2g. H3/2
(8/15) Cd. 2g. H²
(8/15) Cd. 2g. H5/2
When a cylindrical vessel containing liquid is resolved, the surface of the liquid takes the shape of
A triangle
A paraboloid
An ellipse
None of these
A flow in which the volume of a fluid and its density does not change during the flow is called _________ flow.
Incompressible
Compressible
Viscous
None of these
According to equation of continuity,
w1a1 = w2a2
w1v1 = w2v2
a1v1 = a2v2
a1/v1 = a2/v2
Specific weight of water in S.I. units is equal to
1000 N/m3
10000 N/m3
9.81 × 103 N/m3
9.81 × 10⁶ N/m3
The angle of contact in case of a liquid depends upon
The nature of the liquid and the solid
The material which exists above the free surface of the liquid
Both of die above
Any one of the above
Reynolds number is significant in
Supersonics, as with projectile and jet propulsion
Full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.
Simultaneous motion through two fluids where there is a surface of discontinuity, gravity forces, and wave making effect, as with ship's hulls
All of the above
Center of buoyancy is the
Centroid of the displaced volume of fluid
Center of pressure of displaced volume
Does not exist
None of the above
The magnitude of water hammer depends upon the
Elastic properties of the pipe material
Elastic properties of the liquid flowing through the pipe
Speed at which the valve is closed
All of the above
The value of the coefficient of compressibility for water at ordinary pressure and temperature in kg/cm is equal to
2100
2700
10,000
21,000
A liquid would wet the solid, if adhesion forces as compared to cohesion forces are
Less
More
Equal
Less at low temperature and more at high temperature
Kinematic viscosity is equal to
Dynamic viscosity/density
Dynamic viscosity × density
Density/dynamic viscosity
1/dynamic viscosity × density
The velocity through a channel of circular section will be maximum when the depth of water is __________ the diameter of the circular channel.
0.34 times
0.67 times
0.81 times
0.95 times
To avoid vaporisation in the pipe line, the pipe line over the ridge is laid such that it is not more than
2.4 m above the hydraulic gradient
6.4 m above the hydraulic gradient
10.0 m above the hydraulic gradient
5.0 above the hydraulic gradient